1. Field of the Invention
The present invention relates to a method of fabricating a group III-V nitride compound semiconductor in which a group III-V nitride compound semiconductor including nitrogen (N) is grown using a metal organic chemical vapor deposition (MOCVD) method and the method of fabricating a semiconductor device employing the method of fabricating a group III-V nitride compound semiconductor.
2. Description of the Related Art
In recent years, a group III-V nitride compound semiconductor such as gallium nitride (GaN) has come to the fore as a promising material for a semiconductor comprising a light-emitting device capable of emitting in a visible region from green to blue or in a ultraviolet region, a high-frequency electron device, or an environment-resistant electron device. More specifically, the group III-V nitride compound semiconductor has received great attention when the light-emitting diode (LED) employing the group III-V nitride compound semiconductor came into practical use. Further, practical realization of a semiconductor laser (LD) using the group III-V nitride compound semiconductor has been reported. Therefore, the desire for application of the group III-V nitride compound semiconductor, including a optical disk device as a light source, has arisen.
Such a group III-V nitride compound semiconductor is generally fabricated by growing it on a substrate made of sapphire or a substrate made of silicon nitride (SiC). Examples of methods for growing the group III-V nitride compound semiconductor are the MOCVD method or a molecular beam epitaxy (MBE) method. Among these methods, the MOCVD method is practically effective because it does not require a high vacuum state. Thus, the MOCVD is frequently used.
Conventionally, when the group III-V nitride compound semiconductor is grown using the MOCVD method, along with ammonia (NH3) as a nitrogen source, an organic metal source gas as a source for gallium (Ga), aluminum (Al), indium (In), boron (B) and the like corresponding to the group III-V nitride compound semiconductor to be grown is supplied into a reaction tube of a MOCVD apparatus to grow the group III-V nitride compound semiconductor on the growth surface of a substrate set in the reaction tube.
When the group III-V nitride compound semiconductor not including indium such as GaN or AlGaN mixed crystal is grown using this MOCVD method, the growth temperature is about 1000xc2x0 C. in general. In the case where the group III-V nitride compound semiconductor including indium such as GaInN mixed crystal is grown with the MOCVD method, the growth temperature is generally about 700 to 800xc2x0 C., since in order to suppress decomposition of InN, the growth temperature has to be lower than the growth temperature when the group III-V nitride compound semiconductor constituted with GaN is grown.
However, since ammonia used as a nitrogen source has low decomposition efficiency, only a couple of percent of ammonia is decomposed at a temperature as high as about 1000xc2x0 C. Therefore, nitrogen contributing growth that is supplied onto the growth surface of the substrate during growth is insufficient. As a result, the group III-V nitride compound semiconductor has insufficient nitrogen, which lowers the crystallinity. Specifically, with a GaN light-emitting device which emits a blue-purple light, an active layer (emitting layer) is composed of the group III -V nitride compound semiconductor including indium as a group III element and is grown at a low temperature. Thus, crystallinity of the active layer lowers, resulting in low emission efficiency.
The present invention has been achieved in view of the above problems. It is an object of the invention to provide a method of fabricating a group III-V nitride compound semiconductor in which high crystallinity is achieved without lack of nitrogen, even when it is grown at a low temperature, and a method of fabricating a semiconductor device employing the method of fabricating a group III-V nitride compound semiconductor.
According to the first method of fabricating a group III-V nitride compound semiconductor of the present invention, a group III-V nitride compound semiconductor including at least one selected from group III-V elements and at least nitrogen (N) selected from group V elements is grown using a metal organic chemical vapor deposition method. With this method, the growth temperature is below or equal to 900xc2x0 C., and a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom is used as a nitrogen source.
According to the second method of fabricating a group III-V nitride compound semiconductor of the present invention, a group III-V nitride compound semiconductor including at least one selected from group III elements and at least nitrogen (N) selected from group V elements is grown using a metal organic chemical vapor deposition method. With this method, the growth temperature is below or equal to 900xc2x0 C., and ammonia and a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom is used as a nitrogen source.
According to the third method of fabricating a group III-V nitride compound semiconductor of the present invention, a group III-V nitride compound semiconductor including at least indium (In) selected from group III elements and at least nitrogen (N) selected from group V elements is grown using a metal organic chemical vapor deposition method. With this method, a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom is used as a nitrogen source.
According to the fourth method of fabricating a group III-V nitride compound semiconductor of the present invention, a group III-V nitride compound semiconductor including at least indium (In) selected from group III elements and at least nitrogen (N) selected from group V elements is grown using a metal organic chemical vapor deposition method. With this method, ammonia and a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom is used as a nitrogen source.
According to the first method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor layer including at least one of group III elements and at least nitrogen (N) selected from group V elements is provided. With this method, the group III-V nitride compound semiconductor layer is grown at a growth temperature below or equal to 900xc2x0 C. with a metal organic chemical vapor deposition method using a nitrogen including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
According to the second method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor layer including at least one selected from group III elements and at least nitrogen (N) selected from group V elements is provided. With this method, the group III-V nitride compound semiconductor layer is grown at a growth temperature below or equal to 900xc2x0 C. with a metal organic chemical vapor deposition method using ammonia and a nitrogen including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
According to the third method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor layer including at least indium (In) selected from group m elements and at least nitrogen (N) selected from group V elements is provided. With this method, the group III-V nitride compound semiconductor layer is grown with a metal organic chemical vapor deposition method using a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
According to the fourth method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor layer including at least indium (In) selected from group III elements and at least nitrogen (N) selected from group V elements is provided. With this method, the group III-V nitride compound semiconductor layer is grown with a metal organic chemical vapor deposition method using ammonia and a nitrogen including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
With the first method of fabricating a group III-V nitride compound semiconductor and the first method of fabricating a semiconductor device of the present invention, the group III-V nitride compound semiconductor is grown at a growth temperature below or equal to 900xc2x0 C. with a metal organic chemical vapor deposition method using a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
With the second method of fabricating a group III-V nitride compound semiconductor and the second method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor is grown at a growth temperature below or equal to 900xc2x0 C. with a metal organic chemical vapor deposition method using ammonia and a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
With the third method of fabricating a group III-V nitride compound semiconductor and the third method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor including indium is grown with a metal organic chemical vapor deposition method using a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
With the fourth method of fabricating a group III-V nitride compound semiconductor and the fourth method of fabricating a semiconductor device of the present invention, a group III-V nitride compound semiconductor including indium is grown with a metal organic chemical vapor deposition method using ammonia and a nitrogen-including compound having at least one of a single bond of nitrogen atoms, a double bond of nitrogen atoms and a single bond of a nitrogen atom and a carbon atom as a nitrogen source.
Other and further objects, features and advantages of the invention will appear more fully from the following description.